Struct LookupAnyManager

pub struct LookupAnyManager<F: Field + Ord, const ADVICE_COLS: usize> {
    pub cells_to_lookup: Arc<Mutex<BTreeMap<ContextTag, Vec<[AssignedValue<F>; ADVICE_COLS]>>>>,
    /* private fields */
}

A manager that can be used for any lookup argument. This manager automates the process of copying cells to designed advice columns with lookup enabled. It also manages how many such advice columns are necessary.

Detailed explanation

If we have a lookup argument that uses ADVICE_COLS advice columns and TABLE_COLS table columns, where the table is either fixed or dynamic (advice), then we want to dynamically allocate chunks of ADVICE_COLS columns that have the lookup into the table always on so that:

• every time we want to lookup [_; ADVICE_COLS] values, we copy them over to a row in the special lookup-enabled advice columns.
• note that just for assignment, we don’t need to know anything about the table itself. Note: the manager does not need to know the value of TABLE_COLS.

We want this manager to be CPU thread safe, while ensuring that the resulting circuit is deterministic – the order in which the cells to lookup are added matters. The current solution is to tag the cells to lookup with the context id from the Context in which it was called, and add virtual cells sequentially to buckets labelled by id. The virtual cells will be assigned to physical cells sequentially by id. We use a BTreeMap for the buckets instead of sorting to cells, to ensure that the order of the cells within a bucket is deterministic. The assumption is that the Context is thread-local.

Cheap to clone across threads because everything is in Arc.

Fields

cells_to_lookup: Arc<Mutex<BTreeMap<ContextTag, Vec<[AssignedValue<F>; ADVICE_COLS]>>>>

Shared cells to lookup, tagged by (type id, context id).

Implementations

impl<F: Field + Ord, const ADVICE_COLS: usize> LookupAnyManager<F, ADVICE_COLS>

pub fn copy_manager(&self) -> &SharedCopyConstraintManager<F>

Global shared copy manager

impl<F: Field + Ord, const ADVICE_COLS: usize> LookupAnyManager<F, ADVICE_COLS>

pub fn witness_gen_only(&self) -> bool

Specify whether constraints should be imposed for additional safety.

impl<F: Field + Ord, const ADVICE_COLS: usize> LookupAnyManager<F, ADVICE_COLS>

pub fn set_copy_manager( &mut self, val: SharedCopyConstraintManager<F>, ) -> &mut Self

Global shared copy manager

impl<F: Field + Ord, const ADVICE_COLS: usize> LookupAnyManager<F, ADVICE_COLS>

pub fn new( witness_gen_only: bool, copy_manager: SharedCopyConstraintManager<F>, ) -> Self

Creates a new LookupAnyManager with a given copy manager.

pub fn add_lookup( &self, tag: ContextTag, cells: [AssignedValue<F>; ADVICE_COLS], )

Add a lookup argument to the manager.

pub fn total_rows(&self) -> usize

The total number of virtual rows needed to special lookups

pub fn num_advice_chunks(&self, usable_rows: usize) -> usize

The optimal number of ADVICE_COLS chunks of advice columns with lookup enabled for this particular lookup argument that we should allocate.

pub fn clear(&mut self)

Clears state

pub fn deep_clone(&self, copy_manager: SharedCopyConstraintManager<F>) -> Self

Deep clone with the specified copy manager. Unsets assigned.

Trait Implementations

impl<F: Clone + Field + Ord, const ADVICE_COLS: usize> Clone for LookupAnyManager<F, ADVICE_COLS>

fn clone(&self) -> LookupAnyManager<F, ADVICE_COLS>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<F: Debug + Field + Ord, const ADVICE_COLS: usize> Debug for LookupAnyManager<F, ADVICE_COLS>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<F: Field + Ord, const ADVICE_COLS: usize> Drop for LookupAnyManager<F, ADVICE_COLS>

fn drop(&mut self)

Sanity checks whether the manager has assigned cells to lookup, to prevent user error.

impl<F: Field + Ord, const ADVICE_COLS: usize> VirtualRegionManager<F> for LookupAnyManager<F, ADVICE_COLS>

type Config = Vec<[Column<Advice>; ADVICE_COLS]>

The Halo2 config with associated columns and gates describing the physical Halo2 region that this virtual region manager is responsible for.

fn assign_raw(&self, config: &Self::Config, region: &mut Region<'_, F>)

Assign virtual region this is in charge of to the raw region described by config.

type Assignment = ()

Return type of the assign_raw method. Default is ().